A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar
In this case study, a nutrient budget was made to estimate import and export flows of phosphorus (P) on the ecotourism resort of Chumbe Island, Zanzibar. The P content in imported foods and goods was calculated using supply lists containing information on quantities of items bought and standard f...
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| Formato: | Otro |
| Lenguaje: | sueco Inglés |
| Publicado: |
2007
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| Acceso en línea: | https://stud.epsilon.slu.se/11727/ |
| _version_ | 1855571927002775552 |
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| author | Lindström, Bodil |
| author_browse | Lindström, Bodil |
| author_facet | Lindström, Bodil |
| author_sort | Lindström, Bodil |
| collection | Epsilon Archive for Student Projects |
| description | In this case study, a nutrient budget was made to estimate import and export flows of
phosphorus (P) on the ecotourism resort of Chumbe Island, Zanzibar. The P content in
imported foods and goods was calculated using supply lists containing information on
quantities of items bought and standard food composition data. Foods and goods not
included in the standard data were subsampled for P analysis.
Total P import to Chumbe Island was 41.0 kg/year. More P was imported with foods to the guest kitchen than to the staff kitchen (13.2 and 9.1 kg P/year, respectively) although the guest kitchen served fewer meals (9333 and 14113 meals, respectively). This is explained by the more P-rich foods served in the guest kitchen. When charcoal and firewood were included, the staff and guest kitchens imported equal amounts of P since the staff kitchen used both firewood and charcoal while the guest kitchen only used
charcoal as a complement to gas.
Ash and biodegradable waste such as fruit peel were composted on-site and used to
facilitate the degradation process in composting toilets. Biodegradable waste from both
kitchens contributed 4.8 kg P/year to the compost heap, while the ash from kitchen stoves
contributed an estimated max. 17.4 kg P/year. Despite uncertainties regarding P amounts
in the kitchen waste, estimations showed that P was lost from the compost heap during all
stages of decomposition. Animals and birds scattering the compost during feeding and
leaching during the rainy season are possible reasons for these losses.
In the guest kitchen greywater system, sludge and grease were removed before the
greywater was discharged into a small mangrove swamp, while staff kitchen greywater
was poured untreated into a mud-hole in rocky ground. The guest kitchen contributed
slightly more to P discharge (0.3 kg P/year) than the staff kitchen (0.2 kg P/year). The
sludge (discharged at unspecified locations on Chumbe) contained another 0.1 kg P/year.
The grease (added to compost) contained no P.
Food scraps from both kitchens containing 2.4 kg P/year and composted toilet waste
containing 21.6 kg P/year were re-exported to Zanzibar, i.e. approx. half the P imported
was exported. The other half of imported P was lost from compost, greywater outlets, as
sludge or dissipated through fly ash dispersal.
To avoid P accumulation on Chumbe Island, I recommend that all toilet waste and ash be exported in future, since they contain nutrients useful on agricultural land on Zanzibar but harmful to the reef. Furthermore, Chumbe Island management should act to counteract current sources of P losses. |
| format | Otro |
| id | RepoSLU11727 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish Inglés |
| publishDate | 2007 |
| publishDateSort | 2007 |
| record_format | eprints |
| spelling | RepoSLU117272017-11-23T09:18:45Z https://stud.epsilon.slu.se/11727/ A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar Lindström, Bodil Dept. of Soil Sciences Soil biology In this case study, a nutrient budget was made to estimate import and export flows of phosphorus (P) on the ecotourism resort of Chumbe Island, Zanzibar. The P content in imported foods and goods was calculated using supply lists containing information on quantities of items bought and standard food composition data. Foods and goods not included in the standard data were subsampled for P analysis. Total P import to Chumbe Island was 41.0 kg/year. More P was imported with foods to the guest kitchen than to the staff kitchen (13.2 and 9.1 kg P/year, respectively) although the guest kitchen served fewer meals (9333 and 14113 meals, respectively). This is explained by the more P-rich foods served in the guest kitchen. When charcoal and firewood were included, the staff and guest kitchens imported equal amounts of P since the staff kitchen used both firewood and charcoal while the guest kitchen only used charcoal as a complement to gas. Ash and biodegradable waste such as fruit peel were composted on-site and used to facilitate the degradation process in composting toilets. Biodegradable waste from both kitchens contributed 4.8 kg P/year to the compost heap, while the ash from kitchen stoves contributed an estimated max. 17.4 kg P/year. Despite uncertainties regarding P amounts in the kitchen waste, estimations showed that P was lost from the compost heap during all stages of decomposition. Animals and birds scattering the compost during feeding and leaching during the rainy season are possible reasons for these losses. In the guest kitchen greywater system, sludge and grease were removed before the greywater was discharged into a small mangrove swamp, while staff kitchen greywater was poured untreated into a mud-hole in rocky ground. The guest kitchen contributed slightly more to P discharge (0.3 kg P/year) than the staff kitchen (0.2 kg P/year). The sludge (discharged at unspecified locations on Chumbe) contained another 0.1 kg P/year. The grease (added to compost) contained no P. Food scraps from both kitchens containing 2.4 kg P/year and composted toilet waste containing 21.6 kg P/year were re-exported to Zanzibar, i.e. approx. half the P imported was exported. The other half of imported P was lost from compost, greywater outlets, as sludge or dissipated through fly ash dispersal. To avoid P accumulation on Chumbe Island, I recommend that all toilet waste and ash be exported in future, since they contain nutrients useful on agricultural land on Zanzibar but harmful to the reef. Furthermore, Chumbe Island management should act to counteract current sources of P losses. En näringsbudget för ekoturistön Chumbe, Zanzibar, har genomförts för att kunna bedöma import- och exportflödena av fosfor (P). Fosforinnehållet i importerade livsmedel och varor beräknades utifrån inköpslistor, där mängderna av varor var specificerade, och livsmedelsdatabaser. Prover för fosforanalys togs på varor som inte fanns med i databaserna. Totalt importerades 41 kg P per år till Chumbe. Det importerades mer P till gästköket (13.2 kg P/år) än till personalköket (9.1 kg P/år) trots att gästköket tillredde färre måltider (9333 jämfört med 14113). Detta kan förklaras med att gästköket serverar måltider med ett större fosforinnehåll. Personalköket använder både kol och ved medan gästköket bara använder kol som ett komplement till gas. När kol och ved räknades in blev summan av P i importerade livsmedel och varor lika stora i båda köken. Aska och nedbrytbart avfall, såsom fruktskal, komposterades på ön och används sedan för att främja nedbrytning i torrtoaletterna. Tillsammans slängde de båda köken 4.8 kg P/år med det komposterbara avfallet, medan askan tillförde uppskattningsvis upp till 17.4 kg/år till komposthögen. Trots osäkerheter i beräkningen av askans och köksavfallets P innehåll kan en fosforförlust uppskattas från alla steg i komposteringsprocessen, från komposthögen, från den mogna komposten och slutligen från det kompostmaterial som senare används i toaletterna. Detta kan bero på utlakande regn och på de djur och fåglar som sprider kompostmaterialet då de äter av den. Gästköket har ett gråvattensystem där slam och fett avskiljs från vattnet innan det hälls ut i ett litet mangroveträsk medan personalköket häller ut sitt gråvatten orenat i en lerpöl. Trots detta släppte gästköket ut mer P (0.3 kg P/år) än personalköket (0.2 kg P/år). Dessutom innehöll slammet, som tömdes på olika ställen på eller utanför ön, ytterligare 0.1 kg P/år. Fettet, som las på komposten, innehöll inget P. Exporterat tillbaka till Zanzibar blev matresterna från båda köken, som uppskattades innehålla 2.4 kg P/år, och det komposterade toalettavfallet (21.6 kg P/år), dvs. hälften av det importerade P. Den andra hälften förlorades från komposten, vid gråvattenutloppen, som slam eller med flygaska. För att undvika upplagring av P på ön Chumbe bör all aska och toalettkompost i fortsättningen exporteras eftersom de innehåller näringsämnen som är användbara i jordbruket på Zanzibar men är skadliga för korallrevet utanför ön. Personalen bör också se över de platser där det för närvarande sker P utsläpp. 2007-12-06 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/11727/1/lindstrom_b_171123.pdf Lindström, Bodil, 2007. A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar. UNSPECIFIED, Uppsala. Uppsala: (NL, NJ) > Dept. of Soil Sciences <https://stud.epsilon.slu.se/view/divisions/4023.html> urn:nbn:se:slu:epsilon-s-9054 eng |
| spellingShingle | Dept. of Soil Sciences Soil biology Lindström, Bodil A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title | A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title_full | A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title_fullStr | A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title_full_unstemmed | A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title_short | A phosphorus budget for the eco-tourist resort of Chumbe Island Coral Park, Zanzibar |
| title_sort | phosphorus budget for the eco-tourist resort of chumbe island coral park, zanzibar |
| topic | Dept. of Soil Sciences Soil biology |
| url | https://stud.epsilon.slu.se/11727/ https://stud.epsilon.slu.se/11727/ |